Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Test methods research

This research was detected the defect of the void and the exfoliation in the solid phase diffusion bonding interface of ductile cast iron and stainless steel with a nickel insert metal using ultrrasonic testing method, and was examined the influence of mutual interference of the reflectional wave both the defect and the interface... [Pg.839]

Fibers in Textiles Identification, AATCC Test Method 20-1973, Technical Manual 50 50, American Association of Textile Chemists and Colorists, Research Triangle Park, N.C., 1974. [Pg.287]

The odor detection-threshold values of organic compounds, water, and mineral oil have been determined by different investigators (Table 2 and 3) and may vary by as much as 1000, depending on the test methods, because human senses are not invariable in their sensitivity. Human senses are subject to adaption, ie, reduced sensitivity after prolonged response to a stimulus, and habituation, ie, reduced attention to monotonous stimulation. The values give approximate magnitudes and are significant when the same techiriques for evaluation are used. Since 1952, the chemistry of odorous materials has been the subject of intense research (43). Many new compounds have been identified in natural products (37—40,42,44—50) and find use in flavors. [Pg.11]

The analytical research and development (R D) unit is often responsible for the preparation and vahdation of test methods. The R D lab is not faced with the same pressures for rapid analysis as the QC unit, where pending results often hold up production. In addition, R D often assigns personnel to specific instmments or techniques, whereas QC generally requires technicians to perform varied analyses. This leads to an expertise on the part of analytical chemists and technicians which is difficult to duphcate in QC. Therefore the R D test method should be mgged enough to withstand the different environment of the QC lab and stiU provide vahd results. [Pg.369]

Researchers had noted the release of formaldehyde by chemically treated fabric under prolonged hot, humid conditions (85,86). The American Association of Textile Chemists and Colorists (AATCC) Test Method 112 (87), or the sealed-jar test, developed in the United States and used extensively for 25 years, measures the formaldehyde release as a vapor from fabric stored over water in a sealed jar for 20 hours at 49°C. The method can also be carried out for 4 hours at 65°C. Results from this test have been used to eliminate less stable finishes. [Pg.446]

CEFIC has undertaken a wide-ranging programme of research in cooperation with similar organizations throughout the world. The major topics covered by this three-year programme, costing 7m in Europe and 20m worldwide, are male reproductive health, wildlife exposure and testing methods. [Pg.25]

The importance of the method in corrosion testing and research has stimulated other work, and since Stern s papers appeared there have been a number of publications many of which question the validity of the concept of linear polarisation. The derivation of linearity polarisation is based on an approximation involving the difference of two exponential terms, and a number of papers have appeared that have attempted to define the range of validity of polarisation resistance measurements. Barnartt" derived an analytical expression for the deviations from linearity and concluded that it varied widely between different systems. Leroy", using mathematical and graphical methods, concluded that linearity was sufficient for the technique to be valid in many practical corrosion systems. Most authors emphasise the importance of making polarisation resistance measurements at both positive and negative overpotentials. [Pg.1012]

In this test for transparent plastics, the loss of optical effects is measured when a specimen is exposed to the action of a special abrading wheel. In one type of test the amount of material lost by a specimen is determined when the specimen is exposed to falling abrasive particles or to the action of an abrasive belt. In another test, the loss of gloss due to the dropping of loose abrasive on the specimen is measured. The results produced by the different tests may be of value for research and development work when it is desired to improve a material with respect to one of the test methods. The variables that enter into tests of this type are... [Pg.330]

The link between laboratory abrasion methods and road tests is now well established so that further research can concentrate on further elucidation of the basic underlying processes. This concerns particularly the interaction between filler systems and polymers, which is continuously expanding through both new polymers and new fillers. But now the link does not extend from a basic experiment to tire road testing. It can be limited to a laboratory abrasion testing method and suitable basic experiments. [Pg.759]

The Knoop test is a microhardness test. In microhardness testing the indentation dimensions are comparable to microstructural ones. Thus, this testing method becomes useful for assessing the relative hardnesses of various phases or microconstituents in two phase or multiphase alloys. It can also be used to monitor hardness gradients that may exist in a solid, e.g., in a surface hardened part. The Knoop test employs a skewed diamond indentor shaped so that the long and short diagonals of the indentation are approximately in the ratio 7 1. The Knoop hardness number (KHN) is calculated as the force divided by the projected indentation area. The test uses low loads to provide small indentations required for microhardness studies. Since the indentations are very small their dimensions have to be measured under an optical microscope. This implies that the surface of the material is prepared approximately. For those reasons, microhardness assessments are not as often used industrially as are other hardness tests. However, the use of microhardness testing is undisputed in research and development situations. [Pg.29]

Source U.S. EPA, Requirements for Hazardous Waste Landfill Design, Construction, and Closure, EPA/625/4-89/022, U.S. Environmental Protection Agency, Cincinnati, OH, August 1989. a U.S. Army Corps of Engineers Test Method. b Geosynthetic Research Institute Test Method. [Pg.1131]

Focusing on validation process of in vitro methods, it is possible to underline some differences between tools for research and ones for toxicological testing. A research model is validated when there are some specific evidences confirming that the information from the model is able to correctly describe the process in the intact animal. Tools for toxicity testing are often used to evaluate safety hypothesis so they can be used without requiring in vivo confirmation. They are validated using a subset of well-known materials and, once validated, systems will be applied to new unknown materials or mixtures in order to evaluate their toxicity and compare their potential with other chemicals. [Pg.78]

Brandon, E.F., Raap, C.D., Meijerman, I. etal. (2003) An update on in vitro test methods in human hepatic drug biotransformation research pros and cons. Toxicology and Applied Pharmacology, 189 (3), 233-246. [Pg.57]

In a joint research project in Sweden under the main title "Fire hazard - Fire growth in compartments in the early stage of development (pre-flashover)" (1, 2) a number of different factors have been studied. In the process of developing a full-scale fire test method - "room-corner" configuration - for surface lining materials, Nordtest NT-FIRE 025, the emission of smoke and gas was studied. That study covers data from thirteen different single and... [Pg.35]

King, P. V., and A. H. Lasseigne, "Hazard Classification of Explosives for Transportation Evaluation Test Methods, Hazard Evaluation, Research, and Engineering," Report No. TSA-20-72-5, prepared for U. S. Dept, of Transportation (1972) (available from NTIS, Springfield, VA). [Pg.184]

The lowest temperature of a flammable liquid at which it gives off sufficient vapor to form an ignitable mixture with the air near the surface of the liquid or within the vessel used. The flash point has been commonly determined by the open cup or closed cup method but recent research has yielded higher and lower flash points dependent on the surface area of the ignition source. Because of this aspect ASTM and other standard test methods have been recently withdrawn. They are under review until an adequate determination of a practical and comprehensive standard is composed and agreed upon. [Pg.29]

Standard Research Test Method for Determining Smoke Generation of Solid Materials (similar to ASTM E 662). [Pg.264]

This chapter is concerned with the design and improvement of chemically-active ship bottom paints known as antifouling paints. The aims have been to illustrate the challenges involved in working with such multi-component, functional products and to show which scientific and engineering tools are available. The research in this field includes both purely empirical formulation and test methods and advanced tools including mathematical modelling of paint behaviour. [Pg.181]


See other pages where Test methods research is mentioned: [Pg.25]    [Pg.472]    [Pg.475]    [Pg.301]    [Pg.159]    [Pg.311]    [Pg.351]    [Pg.2317]    [Pg.2436]    [Pg.348]    [Pg.26]    [Pg.80]    [Pg.238]    [Pg.1013]    [Pg.22]    [Pg.24]    [Pg.977]    [Pg.1450]    [Pg.68]    [Pg.35]    [Pg.91]    [Pg.515]    [Pg.37]    [Pg.268]    [Pg.55]    [Pg.78]    [Pg.48]    [Pg.131]    [Pg.77]    [Pg.13]    [Pg.322]   
See also in sourсe #XX -- [ Pg.377 ]




SEARCH



Research methods

© 2024 chempedia.info